Steven Hawking added his voice to a growing chorus of experts concerned that AI and automation are going to decimate middle class jobs, worsen inequality, and increase the risk of significant political upheaval.

A report put out in February 2016 by Citibank with the University of Oxford predicted that 47% of US jobs are at risk of automation. In the UK, 35% are. In China, it’s a whopping 77%. Hawking writes that automation will, ” accelerate the already widening economic inequality around the world. The internet and the platforms that it makes possible allow very small groups of individuals to make enormous profits while employing very few people. This is inevitable, it is progress, but it is also socially destructive.”

This is what I’ve said for some time. AI allows you to replace whole swaths of employees. We can see how this is playing out by looking at the economies AirBnB and Uber are setting up. Instead of these nationwide chains of workers facilitating this new industry, the work is largely done by servers and AI on commoditized server farms. Instead of that money coming into a company of thousands, machine learning and automation can do it with only hundreds. Those hundreds are in narrow job titles with many traditional disciplines no longer needed. Further, it’s not hard to see how this concentrates money from a nation-wide chain into an incredibly small number of pockets instead of a host of employees they might have hired in years past.

Don’t get me wrong, I’m not for putting our heads in the sand and ignoring these new economies or saying we should stop them. That’s impossible. However, as Hawking and economists note, “We are living in a world of widening, not diminishing, financial inequality, in which many people can see not just their standard of living, but their ability to earn a living at all, disappearing. It is no wonder then that they are searching for a new deal, which Trump and Brexit might have appeared to represent.”

So what will be lost and what will be left? Just like the industrial revolution – certain kinds of jobs will be affected, but others will not. Creative, supervisory, and health care roles are likely safe. Skilled workers that know how to build and maintain AI server systems as well. But jobs like cashiers, tellers, secretaries, logistics, quantitative marketing/planning/strategy, financial planning, truck drivers, possibly even train conductors or airline pilots could all see major parts of their job functions replaced with machine learning algorithms. We’re already seeing this with automated checkouts, automated driving vehicles, and logistics AI’s are already out-performing replacing live counterparts. Even if one’s job is not replaced, there might only need to be one or two persons in the cockpit instead of 3 to 5.

This is going to come to a head in our lifetimes, and it’s very important we start talking and thinking about it now.